Process and system for selectable data transmission

ABSTRACT

Method and/or system for use in selectable data transmission. An electronic key may be generated (e.g., by a central module) and stored as assigned to authentication data. Electronic data may then be encrypted (e.g., by the central module) into encrypted data using at least part of the electronic key. A signaling message may be transmitted (e.g., by the central module) to a first communications terminal, and the encrypted data may then be transmitted (e.g., by the central module) to a second communications terminal that is selected by the first communications terminal. At least part of the electronic key may then be transmitted (e.g., by the central module) to the second communications terminal. The encrypted data may be decrypted by the second communications terminal using the at least part of the electronic key.

CROSS REFERENCE TO RELATED APPLICATIONS

This patent specification is based on European patent application, No.06116806.8 filed on Jul. 7, 2006 in the European Patent Office, theentire contents of which are incorporated by reference herein.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a process and a system for selectabledata transmission.

2. Description of the Related Art

In the state of the art, data that are present on a network, e.g. datastored on a network server, are often accessed from a terminal, e.g.from a computer of a user. Thus, a user can, for example, use a terminalin order to retrieve E-mail messages that are stored on an E-mailserver. In the state of the art, various processes are known for thetransmission of data between a server and a terminal. Processes areknown that are particularly suitable for transmitting E-mail messages orcurrent headlines. Processes are known for transmitting multimedia data,such as audio data or video data, from a network server to a terminal.Such processes can be based, for example, on protocols such as POP (PostOffice protocol), IMAP (Internet Message Access Protocol), FTP (FileTransfer Protocol), SMB (Server Message Block) or any other kind ofprotocol.

Before data are transmitted, a check can be made on whether a user isentitled to access the corresponding data. Before E-mail messages areaccessed, or before an audio file is downloaded, for example, theidentity of a user is checked, by means of a user name and a password,for example, or, in other words, authentication is carried out. Suchauthentication can also be based, for example, on the creation of asecured data connection, such as a VPN connection (VPN: Virtual PrivateNetwork). After the check on the identity of the user, correspondingdata are transmitted to the terminal of the user, whereupon the data areavailable to the user on this terminal.

Depending on the nature of the data, however, and depending on thenature of the terminal, it can be problematic for the user to access thedata. Special software may be required, for example, in order to accessthe data. Or it may be necessary for the terminal to possess specificfeatures, such as a particularly powerful processor, a particularlyhigh-resolution screen, particular input devices, such as a precisemouse or a joystick, or any other kind of input/output devices, in orderto display or represent the data on the terminal. A user often possessesvarious terminals, e.g. a terminal at home, a mobile terminal, or aterminal at the workplace, whereby these terminals often also displaydifferent features in regard to network bandwidth, processor performanceor screen resolution. After the user has carried out authentication witha terminal and is thus entitled to transmit specific data to theterminal, such as E-mail messages or video data, it would often beconvenient for the user to select a particular terminal in order totransmit the data to that terminal. Thus, it can be convenient that anE-mail message with a video file is better transmitted to the terminalat home or that an E-mail message with a presentation is bettertransmitted to the terminal at the workplace. In order to carry out sucha transmission of the data in the state of the art, the user must carryout authentication with the appropriate terminal and then initiate thetransmission of the data to the terminal. In the state of the art, dataare downloaded by the user to the same terminal on which therepresentation of the data also takes place.

In the state of the art, for the reasons mentioned, the transmission ofdata from a server to a terminal of a user, for example, suffers fromvarious disadvantages. A user could, of course, initially download datato a terminal on which the user is working at the time, and thenretransmit the data to a preferred terminal. Such a transmission iscomplicated, however, and is not feasible at all under somecircumstances, for example, because of a lack of capacity of the networkinterface of the terminal, such as, for example, the capacity of thenetwork interface of a mobile terminal. Without additionalauthentication mechanisms, moreover, the data transmitted to thepreferred terminal could easily be looked at by a third party who wasusing that terminal at the time.

The document WO 2005/020541 discloses a method for the secure transferof content from a content server to a content consumer. A contentrequestor sends instructions so that a content access code istransmitted to the content consumer. On the basis of the content accesscode, a request is sent by the content server for the encryption ofcontent and for the downloading of the encrypted content to the contentserver.

The document WO 01/11883 discloses a method for the safe circulation ofcontent. A content provider provides content to a service provider. Theservice provider provides the content to at least one content consumer.A confidence-based relationship can exist between the content providerand the service provider, as well as between the service provider and atleast one content consumer, so that the content is protected both duringtransmission and during reception within a broadcast or multicastnetwork.

SUMMARY OF THE INVENTION

The present inventions include a new process and a new system forselectable data transmission which overcome the disadvantages of theprior art.

According to the present inventions, these objectives are achieved inparticular by the elements of the independent claims. In addition,further advantageous embodiments emerge from the dependent claims andthe description.

These objectives are achieved by the present inventions in particular bythe fact that authentication data and an electronic key are generated,whereby the electronic key is stored as assigned to the authenticationdata, that data are encrypted by means of an encryption module of acentral module and by means of at least part of the electronic key, thatby means of a transmission module of the central module a signalingmessage is transmitted to a first communications terminal, that by meansof the first communications terminal a second communications terminal isselected, whereby an identification of the selected secondcommunications terminal is transmitted to the transmission module of thecentral module, that the encrypted data are transmitted by thetransmission module of the central module to the second communicationsterminal based on the identification of the selected secondcommunications terminal, that on the basis of a transmission ofauthentication data between the first and/or the second and/or a thirdcommunications terminal and an authentication module of the centralmodule, at least part of the electronic key is transmitted to the secondcommunications terminal, and that by means of a decryption module of thesecond communications terminal and by means of at least part of theelectronic key, the encrypted data are decrypted. Such a process has theparticular advantage that a selectable data transmission can be carriedout, whereby a user can select the communications terminal to which dataare to be transmitted, and whereby it is ensured that only authorizedpersons can access the transmitted data. Such a selectable datatransmission can also refer, for example, to a transmission of a videostream or to a video call, so that, for example, the user on the firstcommunications terminal receives the notification that data concerning avideo stream is ready, that the user by means of the firstcommunications terminal selects a second communications terminal, thatthe encrypted video stream is forwarded to the second communicationsterminal, that by means of the first or second communications terminalauthentication is carried out, and that the electronic key fordecrypting the video stream is transmitted to the second communicationsterminal.

In one embodiment of the present invention, the electronic key isgenerated based on the identification of the second communicationsterminal transmitted to the transmission module of the central module,and/or an encryption algorithm of the encryption module is selectedbased on the identification transmitted to the transmission module ofthe central module. The encryption module can have a number of differentencryption algorithms at its disposal. Depending on the electronic keygenerated, an encryption algorithm suitable for this key can be used.Or, depending on the identification of the second communicationsterminal, an encryption algorithm particularly well adapted to thiscommunications terminal can be selected. So a different electronic keycan be used, depending on the second communications terminal. If, forexample, the second communications terminal is a computer in a firm, anelectronic key can be used that provides a high degree of security. Orif, for example, the second communications terminal is a mobilecomputer, an electronic key can be used that enables efficientdecryption. Such a process has the particular advantage that theencrypted data can be adapted to the second communications terminal.

In another embodiment of the present invention, at least part of theelectronic key is transmitted over a communications link between thecentral module and the first communications terminal and over acommunications link between the first communications terminal and thesecond communications terminal. This embodiment is sensible, forexample, if the first communications terminal is a mobile radio terminalthat can be logged in and authenticated on a mobile radio network. Sothe electronic key can be transmitted to the mobile radio terminal ofthe user, for example, after the user has selected a secondcommunications terminal with the mobile radio terminal and after thedata have been encrypted. The encrypted data can then be transmitted tothe second communications terminal. As soon as the user wishes to accessthe encrypted data with the second communications terminal, theelectronic key can be transmitted from the mobile radio terminal to thesecond communications terminal, for example, over a wirelesscommunications link between the mobile radio device and the secondcommunications terminal. Such a process has the particular advantagethat the electronic key for decrypting the encrypted data always remainsunder the control of the user and is easily available to the user.

In one embodiment of the present invention, a user profile is stored inthe central module, whereby data are encrypted in accordance with theuser profile. So it can be stored in the user profile that, for example,the latest order information for a product or the latest E-mail messagesfor the user are encrypted, whereby a corresponding signaling message isthen transmitted to a first communications terminal of the user. Such aprocess has the particular advantage that the encryption andtransmission of data can be automated in accordance with the guidelinesof the user.

In another embodiment of the present invention, the availability of thesecond communications terminal is checked by means of an availabilitymodule of the central module and, if the second communications terminalis available, the encrypted data are transmitted to the secondcommunications terminal. In this context, availability can mean that anetwork interface of the second communications terminal is ready toreceive. Availability can however also mean that, as a consequence ofoverloading of the capacity of the corresponding networks, thecommunications link between the transmission module and the secondcommunications terminal is classified as not available. Such a processhas the particular advantage that the encrypted data can be transmittedto the second communications terminal at the earliest possible time orwhen the utilization of network capacity is at a definable level.

In another embodiment of the present invention, the encrypted data canbe transmitted to a network device of a network infrastructure, wherebythe encrypted data are stored on the network device, and are transmittedasynchronously by the network device to the second communicationsterminal. Thus, the network device can refer, for example, to a networkstorage device of a private ADSL connection of a residence, connected toan ADSL modem. In this process, the ADSL modem and the network storagedevice remain permanently switched on and the encrypted data can thus betransmitted to the network storage device over the ADSL connection atany time. As soon as the user switches on his computer at home, theencrypted data stored on the network storage device can be transmittedto the computer of the user. Or at a public location, such as a railwaystation with a WLAN access point that has at its disposal an airinterface with a bandwidth of many Mbit/s, but is connected to a networkinfrastructure over a data line with only few Mbit/s, large quantitiesof encrypted data can be transmitted to the WLAN access point at nightand temporarily stored, for example. As soon as the user passes the WLANaccess point at the railway station in the morning, encrypted data canbe transmitted over the powerful air interface to a mobile computer ofthe user. Such a process has the particular advantage that the capacityutilization of network infrastructures can be optimized. So thetransmission of encrypted data over an ADSL connection can take place inthe afternoon, for example, at a time when as yet only few private usersare using the network infrastructure of an Internet provider. A localnetwork in a residence normally has a much higher bandwidth than an ADSLconnection. The transmission from the network memory to the computer ofthe user takes a correspondingly much shorter time than a transmissionover an ADSL connection. For the case described of a WLAN access point,similar advantages result.

In another embodiment of the present invention, a user account isdebited with a monetary value upon the transfer of at least part of theelectronic key. Such a process has the particular advantage thatchargeable services, such as the provision of audio or video files, orany other file, or any other service, such as the intermediate storageof data, the administration of data, or any other service, can beoffered to the user by means of the transmission of encrypted data.

In a further embodiment of the present invention, the encrypted datainclude a program code that must be executed in order to decrypt theencrypted data, while validation criteria are checked during theexecution of the program code. The program code can, for example, be ofsuch form that the validity of the key is checked with reference to atime measurement, to a central server with which the validity of keys ismonitored, or in accordance with any other process. Such a process hasthe particular advantage that, for example, a time can be defined afterwhich the encrypted data are no longer available. Such a processmoreover guarantees compatibility with processes known from DRM (DRM:Digital Rights Management).

In another embodiment of the present invention, an identification isassigned to the data and/or to the encrypted data, and theauthentication data are stored as assigned to the identification. Suchan identification can, for example, be formed as the result of a hashfunction of the encrypted data. Such a process has the particularadvantage that authentication for access to the encrypted data can alsobe of different forms with reference to the encrypted data.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of the invention and many of the attendantadvantages thereof will be readily obtained as the same becomes betterunderstood by reference to the following detailed description whenconsidered in connection with the accompanying drawings, wherein:

FIG. 1 shows a block diagram with the individual components for theencryption of data and for selectable transfer of the encrypted data.

FIG. 2 shows a block diagram of the individual components for theauthentication and decryption of the encrypted data.

FIG. 3 shows a block diagram as in FIG. 1, whereby a key S istransmitted to a second communications terminal mPh.

FIG. 4 shows a block diagram as in FIG. 2, whereby the key S istransmitted by the second communications terminal mPh to a firstcommunications terminal oC.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to the drawings, wherein like reference numerals designateidentical or corresponding parts throughout the several views.

In FIG. 1, the reference mark 10 refers to a central module. The centralmodule 10 can, for example, be formed as a software module of a networkserver. The central module 10 can also, of course, be formed completelyas a hardware module with appropriate electronic circuits. In FIG. 1,the reference mark D refers to electronic data. The data D can beelectronic data of any kind, for example E-mail messages, texts,animations, audio files, video files, or electronic data of any otherkind. In FIG. 1, the reference mark A refers to authentication data andthe reference mark S refers to an electronic key. The authenticationdata A can, for example, include a user name and a password or passphrase. The electronic key S can, for example, include a symmetricalelectronic key with a secret key or an asymmetrical electronic key witha public key and a private key. The authentication data A are stored asassigned to the electronic key S while, for example, the central module10 includes a corresponding table. The authentication data A and theelectronic key S can moreover be stored as assigned to an identificationiD of the data, so that the authentication data A and the electronic keyS are valid only with reference to data that can be identified by theidentification iD of the data. Corresponding tables can of course alsobe provided for in the central module 10 with reference to theidentification iD of the data. Data D can be encrypted by means of theelectronic key S and an encryption module of the central module 10. Suchencryption can refer to any encryption algorithm, for example a DESalgorithm (DES: Data Encryption Standard), a PGP algorithm (PGP: PrettyGood Privacy), an IDEA algorithm (IDEA: International Data EncryptionAlgorithm), or any other encryption algorithm. Encrypted data vD aregenerated by the encryption of the data D.

In FIG. 1, the reference mark mPh relates to a first communicationsterminal. The first communications terminal can be a mobile radiotelephone, a mobile computer, or any other communications terminal. InFIG. 1, the reference mark sM relates to a signaling message. Thesignaling message can be a message in accordance with the SMS standard(SMS: Short Message Service), the USSD standard (USSD: UnstructuredSupplementary Service Data), the SS7 standard (SS7: signaling system#7), the SIP standard (SIP: Session Initiation Protocol) or any otherstandard or any other format. The availability of data D or of encrypteddata vD is signaled to the first communications terminal mPh with thesignaling message sM. The signaling message sM can be transmitted to thefirst communications terminal mPh over any communications network, forexample, over a mobile radio network, over a wireless mobile radionetwork, over a wire-based data network such as an Ethernet network, orover any other communications network. So the signaling message sM caninclude information relating to the availability of E-mail messages,audio data, video data, or any other kind of data. Such information canconcern, for example, the title, the sender, the author, the subjectline, or any other kind of information for the identification of data Dor for the identification of encrypted data vD. The signaling message sMcan be interpreted on the first communications device mPh, andcorresponding information about the availability of data or of encrypteddata can be notified to the user on a display of the firstcommunications terminal. Information relating to second communicationsterminals hC,mC,oC can be notified on the display at the same time.Information relating to second communications terminals hC,mC,oC can betransmitted to the first communications terminal mPh together with thesignaling message sM, or this information can have been stored inadvance on the first communications terminal mPh. A secondcommunications terminal hC,mC,oC can, for example, be a computer, suchas a notebook or a PDA (PDA: Personal Digital Assistant), a mobiletelephone, a games console, a permanently installed computer, or anyother communications terminal. The designation hC relates, for example,to a computer of the user at home, the designation mC relates, forexample, to a mobile computer of the user, and the designation oCdesignates, for example, a computer in an office at a workplace of theuser. The user can select one of the second communications terminalshC,mC,oC, the second communications terminal oC, for example, by meansof an input device of the first communications terminal, a keyboard, amouse, a joystick, for example, or any other input device. Anappropriate message oCM can be transmitted to the central module 10 bymeans of a transmission module of the first communications terminal mPh.Such a message can be interpreted by a transmission module of thecentral module 10, and the encrypted data vD can then be transmitted tothe corresponding second communications terminal oC by means of thetransmission module of the central module 10. However, printers,beamers, or devices of any other kind, which for example are not in thepossession of the user and are used by the user only temporarily, duringa presentation, for example, can also be used as a second communicationsterminal. Thus, by means of the appropriate selection by the firstcommunications terminal mPh, a presentation can be transmitted asencrypted data vD to a computer that is assigned to a beamer. As soon asthe user wishes to start the presentation, the presentation can bedecrypted and presented with the beamer by a corresponding transmissionof the key S. Such a process guarantees that all the data are availableat the start of the presentation, and that the data are only accessibleto the authorized user, in particular without the user having to takewith him a mobile computer of his own. Such a transmission of apresentation to a computer assigned to a beamer is of interest, inparticular, for very large quantities of data, such as a video file.

In FIG. 1, the reference mark 40 refers to a communications network. Thecommunications network can, for example, refer to the Internet and canbe constructed from various networks of differing technologies. Thus,the communications network can include GSM networks, UMTS networks, WLANnetworks, Ethernet networks, UWB networks, or networks of any otherkind. As shown in FIG. 1, the central module 10 and the secondcommunications terminal hC,mC,oC can be connected in particular to thecommunications network 40. The transmission as described of encrypteddata vD to a second communications terminal hC,mC,oC is enabled by meansof the communications network 40. There are the widest variety ofoptions in order thus to store data D as encrypted data vD on the secondcommunications terminal hC,mC,oC. E-mail messages, texts, animations,audio files, video files or data of any other kind can be stored on thesecond communications terminal hC,mC,oC as encrypted E-mail messages,encrypted texts, encrypted animations, encrypted audio files, orencrypted video files. It is, however, the case that the encrypted datavD may still be useless, since for the time being the key to decrypt theencrypted data is stored only on the central module 10.

The transmission of the signaling message sM to the first communicationsterminal mPh and/or the transmission of the encrypted data vD to thesecond communications terminal hC,mC,oC can take place at any favorabletime. A favorable time can refer to the arrival of new E-mail messages,the availability of texts, or the publication of a new audio file. Afavorable time, however, can also refer to the availability of acommunications link between the communications network 40 and the secondcommunications terminal hC,mC,oC, the capacity utilization of thecommunications network 40, the capacity utilization of parts of thecommunications network 40, a time that occurs due to an input from theuser on one of the communications terminals, or any other time.

The transmission of the encrypted data vD can also take place inaccordance with various scenarios. One scenario can be that theencrypted data vD are transmitted to the second communications terminalhC,mC,oC at any time during the night over a broadband communicationslink, such as an Ethernet connection. Such a scenario may be selected,for example, in order to transmit a very large encrypted video file, ofan order of magnitude of 5 Gbytes, for example, to the secondcommunications terminal hC,mC,oC. Or, in another scenario, encrypteddata may be transmitted to the second communications terminal mC as soonas the user with this communications terminal mC comes into the range ofa wireless communications network, such as a WLAN network or UWB networkat a railway station or on the site of an airport. Such a scenario maybe selected, for example, in order to transmit encrypted E-mail messagesor encrypted texts to a user's second communications terminal mC beforehe boards a train. Depending on the network infrastructure, the channelbetween the second communications terminal and the wirelesscommunications network has a much higher bandwidth than the channelbetween the wireless communications network and the backbone of theservice provider. Although data could admittedly be received at highspeed by the second communications terminal, the channel to the backbonecan lead to a severe restriction on the reception rate. For such ascenario, it is advantageous to transmit encrypted data from thebackbone to an intermediate storage device arranged in the wirelesscommunications network ahead of time, during the night, for example. Assoon as the second communications terminal mC is brought into the rangeof the wireless communications network, in the morning, for example,large quantities of encrypted data can be transmitted to the secondcommunications terminal in little time, over a UWB network inparticular. It may be remarked here that encrypted texts may refer, forexample, to the current electronic issue of a daily newspaper.

Depending on the application, the features that the secondcommunications terminal hC,mC,oC has at its disposal are already knownat the time of encryption. Thus, the second communications terminal canrefer, for example, to a mobile computer with a customary VGA screenresolution of 1024×768 pixels. For such a second communications terminalhC,mC,oC, it makes no sense to provide a video file in much higherscreen resolution, for example. Correspondingly, before the encryptionof the data by means of the key S, a transformation of the data D can becarried out so that the data D are already better adapted to the secondcommunications terminal on which the data are to be presented. Such atransformation of the data can only be carried out of course ifcorresponding information is available about the second communicationsterminal. Such information can, for example, be stored in a userprofile.

In FIG. 2, the reference marks introduced in FIG. 1 are retained. Asshown in FIG. 2, authentication data A are transmitted from the secondcommunications terminal hC,mC,oC to the central module 10. The caseusing the second communications terminal oC is outlined in FIG. 2.Entitlement is thus authenticated with the electronic key S. At leastparts of the electronic key S are then transmitted by the central module10 to the second communications terminal hC,mC,oC. By means of theelectronic key S, the encrypted data vD stored on the communicationsterminal can be decrypted and stored as data D on the communicationsterminal, whereby that the user can access the data D.

An authentication of entitlement with the electronic key S can takeplace in accordance with known processes. Such processes can take placeon the basis of a password or pass phrases, by means of a SecureID card(SecureID: authentication process of the firm RSA Security), on thebasis of the acquisition of biometric characteristics, or on any otherbasis that provides proof of entitlement.

Alternatively, the electronic key S can be transmitted to the secondcommunications terminal hC,mC,oC, as shown in FIG. 3 and FIG. 4. As soonas the data D is encrypted into encrypted data vD, the key S used forthis purpose can be transmitted to the first communications terminalmPh. This is particularly sensible if the first communications terminalmPh is a mobile radio terminal logged in on a mobile radio network andthus authenticated. The electronic key S is available to the user of themobile radio terminal. The encrypted data are then transmitted to asecond communications terminal hC,mC,oC in accordance with the selectionmade by the user. As soon as the user uses the corresponding secondcommunications terminal, the key S can be transmitted from the mobileradio terminal to the second communications terminal hC,mC,oC over alocal wireless connection, for example, a Bluetooth connection, forexample, or any other local connection between the mobile radio terminaland the second communications terminal hC,mC,oC, whereupon the encrypteddata vD stored on the second communications terminal hC,mC,oC can bedecrypted into data D, and whereupon the user can access the data D bymeans of the second communications terminal hC,mC,oC.

As indicated in FIGS. 1 to 4 by the dotted fields, the identificationiD, the authentication data A, and the key S can be stored in a tablewith such tuples. Different tuples can also be used for differentapplications. Thus, a first tuple may, for example, be used to encryptvideo data, such as the latest hit films, for a particular secondterminal device, such as a home computer of a user. Or a second tuplecan be used to encrypt the same video data for a mobile computer of theuser. Thus, the same identification iD and the same authentication datacan admittedly be used. On the other hand, the key S can be selected asadapted to the respective terminal device, so that a key with, forexample, different security requirements can be used in each case forthe home computer and for the mobile computer.

The user profiles mentioned can be of such form that they arerespectively tracked dynamically by the first communications device mPh.Thus, when a second communications terminal hC,mC,oC is selected, theuser profiles are dynamically tracked in such a way that, if a signalingmessage sM refers to the same or similar data, the same or a similarsecond communications terminal hC,mC,oC is selected in each case for thetransmission of encrypted data vD. By means of such a user profile, itcan in particular be defined for specific data D which preparation ofthe data D should take place, which key S should be used, and to whichsecond communications terminal hC,mC,oC the encrypted data vD should betransmitted, for example, in the absence of an appropriateidentification by the first communications terminal mPh.

The previously described process may be encoded in software on acomputer readable medium including a compact disk, memory device, flashmemory or any other computer readable physical medium. The software isconfigured to cause a processor-based device to carry out one or more ofthe steps described above. Computer operations are described in “HowComputers Work, Millennium Edition,” by Ron White, Que Publications,1999, the entire contents of which being incorporated herein byreference.

Obviously, numerous modifications and variations of the presentinventions are possible in light of the above teachings. It is thereforeto be understood that within the scope of the appended claims, theinventions may be practiced otherwise than as specifically describedherein.

1-19. (canceled)
 20. A method, comprising: assigning, in a centralmodule, an electronic key to authenticated data associated with aparticular user; Encrypting, in the central module, electronic data intoencrypted data using at least part of the electronic key; transmitting,by the central module, a signaling message that indicates availabilityof the encrypted data or the electronic data, to a first communicationsterminal; transmitting, by the central module, the encrypted data to asecond communications terminal, wherein the second communicationterminal is selected by the first communication terminal; andtransmitting at least part of the electronic key to the secondcommunications terminal to cause decrypting the encrypted data by adecryption module of the second communications terminal using the atleast part of the electronic key.
 21. The method of claim 20, comprisinggenerating the electronic key and/or selecting an encryption algorithmbased on identification of the second communications terminal.
 22. Themethod of claim 20, wherein at least one part of the electronic key istransmitted over a communications link between the central module andthe first communications terminal.
 23. The method of claim 20,comprising storing a user profile in the central module, and wherein theelectronic data is encrypted in accordance with encryption informationspecified in the user profile, and the encrypted data is transmitted tothe second communications terminal when specified in the user profile.24. The method of claim 20, comprising checking by the central module,availability of the second communications terminal, and when the secondcommunications terminal is available, transmitting the encrypted data tothe second communications terminal.
 25. The method of claim 20,comprising transmitting the encrypted data to a network device of anetwork infrastructure, wherein the encrypted data is stored on thenetwork device and is then asynchronously transmitted to the secondcommunications terminal by the network device.
 26. The method of claim20, comprising transforming the electronic data in the central module,prior to the encrypting of the electronic data with the electronic key,such that the electronic data is optimized for use in the secondcommunications terminal.
 27. The method of claim 26, whereintransforming the electronic data comprises optimizing the electronicdata for display on the second communications terminal.
 28. The methodof claim 20, comprising debiting a user account with a monetary valueupon the transfer of at least part of the electronic key.
 29. The methodof claim 20, wherein validation criteria are checked during use of theencrypted data.
 30. The method of claim 20, comprising assigningidentification to the electronic data and/or to the encrypted data, andstoring the authentication data as assigned to the identification.
 31. Asystem, comprising: a central module that is operable to: assign anelectronic key to authenticated data associated with a particular user;encrypt electronic data into encrypted data, using at least part of theelectronic key; transmit a signaling message, that indicatesavailability of the encrypted data or the electronic data, to a firstcommunications terminal; transmit the encrypted data to a secondcommunications terminal, wherein the second communication terminal isselected by the first communication terminal based on the signalmessage; and transmit at least part of the electronic key to the secondcommunications terminal to cause decrypting the encrypted data by adecryption module of the second communications terminal using the atleast part of the electronic key.
 32. The system of claim 31, whereinthe electronic key is generated and/or an encryption algorithm isselected based on identification of the second communications terminal.33. The system of claim 31, wherein the central module is operable totransmit the at least part of the electronic key over a communicationslink between the central module and the first communications terminal.34. The system of claim 31, wherein the central module is operable tostore a user profile, the electronic data being encrypted in accordancewith encryption information specified in the user profile and theencrypted data being transmitted to the second communications terminalwhen specified in the user profile.
 35. The system of claim 31, whereinthe central module is operable to check availability of the secondcommunications terminal, and when the second communications terminal isavailable, the central module being operable to transmit the encrypteddata to the second communications terminal.
 36. The system of claim 31,wherein the central module is operable to transmit the encrypted data toa network device of a network infrastructure, the encrypted data beingstored on the network device with the network device then transmittingthe encrypted data asynchronously to the second communications terminal.37. The system of claim 31, wherein the central module is operable totransform the electronic data, prior to the encrypting of the electronicdata with the electronic key, such that the electronic data is optimizedfor use in the second communications terminal.
 38. The system of claim37, wherein transforming the electronic data comprises optimizing theelectronic data for display on the second communications terminal. 39.The system of claim 31, wherein a user account is debited with amonetary value upon the transfer of at least part of the electronic key.40. The system of claim 31, wherein validation criteria is checkedduring use of the encrypted data.
 41. The system of claim 31, whereinidentification is assigned to the electronic data and/or to theencrypted data and that the authentication data is stored as assigned tothe identification.